TOPIC: Integration to CRM like vtiger

Is there a way to have some kind of integration between dtregister and vtiger or any other CRM, such that we can track membership activities and their event registration

We have no CRM integration at this time. The only thing I can point you towards would be our MyScript plugin. This would enable you to write a custom script that will process after registration that could then send data to some external system. You'd be on your own for actually writing the script, but our plugin could help you to connect the two systems. Just a though for you.